Systems for the synthesis of organic compounds, for example peptides, are highly desired for many applications. For example, the synthesis and collection of a large number of peptides would assist in the development of agents that could block, promote or otherwise affect cellular reactions that involve recognition and binding. These agents would be useful in the treatment or diagnosis of a number of diseases. More particularly, synthetic peptides can be used as diagnostic and therapeutic agents.
Understandably, peptide synthesis systems have been designed and constructed. Houghten. R. A., Proc. Natl Acad. Sci., 82: 5131-5135 (1985), employs a "tea bag" method using standard Boc amino acid resin in polypropylene mesh packets with standard washing, deprotection, neutralization, and coupling protocols of the original solid phase procedure of Merrifield, R. B., J. Amer. Chem Soc., 85: 2149-2154 (1963).
Although some peptide synthesis systems have been automated for the synthesis of multiple peptides, they generally exhibit poor "respite" time, unable to handle efficiently multiple synthetic tasks. For example, commercial peptide synthesis systems, such as those from Gilson, U.S.A. and Advanced Chem Tech, are capable of synthesizing multiple peptide sequences. However, these automated synthesis systems perform each step in the synthetic cycles for all peptides one by one or sequentially. The timing protocol, more specifically, involves washing all peptides one by one, deprotecting all peptides one by one and then coupling all peptides one by one. For example, coupling is initiated for a first peptide and then when those first initiation coupling steps are completed, coupling is initiated for a second peptide. Such a timing protocol results in an especially long delay or respite time between peptide synthesis steps. Washing all peptides one by one is time consuming. Moreover, during coupling, the system is idle while waiting for coupling to finish. With coupling taking up to 2 hours, the efficiency of prior art automated synthesis systems is severely limited.
Furthermore, prior art automated peptide synthesis systems critically lack flexibility. Once the synthesis of a peptide set has started, any additional peptides, even those urgently required, cannot be started. Furthermore, prior art systems lack the flexibility so as to execute more than one type of coupling reaction, which is typically required for the synthesis of non-peptide compounds.